To be funny, comedy must transgress. Slapstick disrupts our sense of physical proportion and propriety, dirty jokes generally mess with our few remaining sexual taboos, and political jokes evoke our deepest responses to the new normal.

But the transgressive punchline must sneak up. Signal the gag too broadly and people might fear it’s a Benny Hill revival; play it too subtly, the audience might not get the comedian’s humour at all.

And if there’s a message in the show, performing it for people who already endorse your views might seem a bit pointless. As often as not, our laughter is fuelled by seeing that the comic’s logic led us to the point where this new absurdity is ineffably right – however momentarily.

In the world of funny people, Ross Noble is a real “what if?” merchant, peddling a collaborative abandonment of common sense. Verbally, he clowns around with the possible in a well-practised stream-of-consciousness style, but also illustrates his punchlines with physical gags drawn from mime.

Still, Noble’s humour is essentially cerebral in that he wants us to follow his running gags and absurdist logic to ridiculous, seemingly improvised, conclusions. Ebola, Gwyneth Paltrow, skip bins and al fresco love – you know it all makes sense.

Riffing off the behaviour and heckles of people close to the stage, Noble seemed to start more shaggy-dog stories than he could possibly finish. Of course, all the loose ends were tied – however loosely – by the end.

At two hours and 40 minutes, Ross Noble – Tangentleman is a bit long. It would have been stronger without unfortunate gags about obese people and a well-intended but long-winded, one-sided jibe at ISIS that left the full house asking “Why?” instead of “WTF?”

But these were minor moments in a show that was, literally, wonderful and worth at least 7/10. (An inside joke, that.)

Ross Noble – Tangentleman is at Thebarton Theatre until March 14.

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